Field
This document relates to an organic electroluminescence display and a driving method thereof.
Related Art
An organic electroluminescence element used for an organic electroluminescence display is a self-luminous element including a light emission layer formed between two electrodes. The organic electroluminescence element is an element in which electrons and holes are injected into the light emission layer from an electron injection electrode (e.g., cathode) and a hole injection electrode (e.g., anode). As excitons formed as the injected electrons and holes are combined fall from the excited state to the ground state, light is emitted.
In the organic electroluminescence display, when a scan signal, a data signal, power, and the like, are supplied to a plurality of subpixels disposed in a matrix, selected subpixels emit light to display an image.
Driving schemes of the organic electroluminescence display are divided into an analog driving scheme for driving the organic electroluminescence device by supplying current or voltage to a display panel and a digital driving scheme for adjusting light emission time. The digital driving scheme includes an ADS (Address Display Separation) driving scheme and an AWD (Address While Display) driving scheme.
In a conventional ADS driving scheme, subframes and addressing time are limited by the frame rate and resolution of a display device, and are under many time constraints because multiple frames are required to achieve sufficient color depth. In a conventional AWD driving scheme, each subframe includes an erasing period for erasing a data signal if required. In this case, the duty cycle (ratio of on time to total light emission time) decreases by an amount equal to the erasing period.
As a consequence, the conventional ADS and AWD driving schemes face numerous difficulties in realizing a large-area, high-resolution display panel due to the aforementioned problems, and thus these problems must be overcome.